<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <title>菜鸟教程(runoob.com)</title>
</head>

<body>

    <p>该实例使用 addEventListener() 方法来向按钮添加点击事件。</p>
    <button id="myBtn">点我</button>
    <p id="demo"></p>
    <script>
        document.getElementById("myBtn").addEventListener("click", function () {
            document.getElementById("demo").innerHTML = "Hello World";
        });
    </script>

</body>

</html>